//! Общий headless-рендер: произвольный Slint-компонент → непустой PNG (План 6 P6.1).

use shturman_render::render_to_png;

slint::slint! {
    export component Probe inherits Window {
        width: 64px; height: 48px; background: #101418;
        Rectangle { background: #ffffff; width: 20px; height: 20px; }
    }
}

#[test]
fn renders_component_to_nonempty_png() {
    let dir = tempfile::tempdir().unwrap();
    let path = dir.path().join("probe.png");
    render_to_png(|| Ok(Probe::new()?), 64, 48, &path).expect("render");

    let dec = png::Decoder::new(std::fs::File::open(&path).unwrap());
    let mut r = dec.read_info().unwrap();
    assert_eq!((r.info().width, r.info().height), (64, 48));
    let mut buf = vec![0u8; r.output_buffer_size()];
    let info = r.next_frame(&mut buf).unwrap();
    let px = &buf[..info.buffer_size()];
    assert!(px.iter().any(|&b| b != px[0]), "кадр одноцветный");
}